Screw-plate



E lf STAT PAN" SCREW-PLATE.

Specification of Letters Patent No.

To all whom it may concern:

Be it known that I, PUTNAM D. NICHOLS, of the city of Hartford, county of Hartford, and State of Connecticut, have invented a new and useful Improvement in the Mode of Constructing Screw Plates and Dies; and I do hereby declare that the following is a correct description thereof, reference being had to the accompanying drawing and to the letters of reference marked thereon.

The nature of my invention consists in the construction of screw plates or stocks with adjustable rotating dies and the mech anism for actuating the same.

To enable others skilled in the art to make and use my invention I will proceed to describe the construction and operation.

The drawing' Figure l is a face view of the screw plate. Iiig. 2 is a sectional view through the middle. F ig. 3 is a back view.

In constructing my screw plate, I adhere to the general principle and method of adjusting the dies by contracting and opening the space for cutting the screw thread.

The form of the plate or stock A as is described in this specification is substantially the same that is generally adopted. No restriction as to size.

The dies B and C I make of a circular form, containing on their periphery a series of various sized screw thread cutters in pairs, each pair numbered and marked so that they, are easilyu and conveniently matched and placed for use. These dies B and C are placed in a sunk recess of the 23,041, dated February 22', 1859.

plate or frame A, and rotate for adjusting when a dierent size screw is required to be cut, and they are held firmly in their position by means of steadying pins in the bottom of the recess, which enters holes at the back of the dies corresponding with the different sized cutters, and are fastened and adjusted by the action of the set screws D, D, which by being unscrewed allows the dies to be lifted o the pins to be turned around and placed on others. The die B, is connected with the sliding plate K, which travels back and forward by the operation of the adjusting screw G and rod I-I, which runs up inside of the handle I, to which it is fastened by the screw pin L and turned by the pin M. Y

The utility of this screw plate consists in the simplicity of construction and in the convenience and compactness for use.

I do not claim as new the circular dies. I/Vhat I claim as my invention, and desire to secure by Letters Patent is- The adjusting steady pins and set screws;

with the sliding plate K attached to the regulating rod and screw G H in the manner as described, in combination with the method of adjusting and regulating the dies for operation, in the manner substantially as set forth.

PUTNAM D` NICHOLS.

Viitnesses:

WVM. VINE, Gro. S. GILMAN, 

